JPH02272870A - Image scanner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image scanner used in, for example, copying machines, facsimile machines, and the like.

BACKGROUND ART Conventionally, as shown in FIG. 5, a housing l having a front cover 2, a lens array 3 in which a plurality of lenses are continuous, an aperture part 4 for narrowing down a light beam, and a roof in which a plurality of roof-shaped reflective surfaces are continuous. A mirror array 5 is arranged in this housing 1,
A light entrance hole 6 and a light exit hole 7 are formed on a straight line passing through the front surface of the lens array 3, and these light entrance holes 6
An optical path converting mirror portion 8 facing the lens array 3 is formed on the front cover 2 between the light exit hole 7 and the light source 11 facing the object surface 9 such as a document placed on the contact glass 10. A light beam from the light source 11 is irradiated onto the object surface 9 by an opposing reflecting plate 16 facing the light source 11, an image of the object surface 9 is incident through the light entrance hole 6, and the incident light is reflected by the optical path conversion mirror section 8. , further, an imaging element that passes through the lens array 3 and is reflected by the roof mirror array 5, passes through the lens array 3 again, is reflected by the optical path conversion mirror section 8, and is imaged from the light exit hole 7 onto the imaging plane. There is.

Recently, light sources 11 such as small cold cathode discharge tubes (commonly known as Xe discharge tubes) with a small diameter of about 4 to 6φ and high illumination efficiency have been developed.
When the light source 11 is brought close to the lens array 3, the flare of the light source 11 is directly irradiated from the light entrance hole 6 to the lens array 3, as shown by the diagonal lines in FIG.

Therefore, in order to block this flare, as shown in FIG. 7, the invention described in JP-A-61-106919 and the invention described in JP-A-60-102.612 as shown in FIG. There is. That is, in the one shown in FIG. 7, the flare of the light source 11 is blocked by a light blocking plate 17. In addition, the one shown in FIG. 8 is provided with an opposing reflecting plate 18 facing the object plane 9 and the light source 11, and a plurality of slits 19 and a light shielding part 20 are provided between the opposing reflecting plate 18 and the light source 11. A slit light-shielding plate 21 is provided, and the light beam from the light source 11 is irradiated through the slit 19 onto the opposing reflecting plate 18, so that the object surface 9 is illuminated by the opposing reflecting plate 18. 21 to block light.

Problems to be Solved by the Invention What is shown in FIG. 7 is that when a structure is adopted in which the light beam from the light source 11 is reflected onto the object surface 9 by an opposing reflecting plate (not shown), the relative position with respect to the light shielding plate 17 is determined. It is difficult to adjust the position of the opposing reflector because of the need to Alternatively, the light beam from the light source 11 is blocked by the light shielding plate 17, resulting in extremely low efficiency. Further, in the case shown in FIG. 8, the number of parts increases because the slit light shielding plate 21 must be provided independently.
It is very difficult to accurately position the slit light shielding plate 21 and form the slits 19.

Means for Solving the Problem A straight line passing through the front surface of the lens array is provided in a housing that includes a lens array in which a plurality of lenses are continuous, a diaphragm that narrows down the luminous flux, and a roof mirror array in which a plurality of roof-shaped reflective surfaces are continuous. forming a light entrance hole facing the object surface on which an image is formed and a light exit hole facing the reading unit, and facing the lens array between the light entrance hole and the light exit hole; An optical path converting mirror section is provided, and an opposing reflecting surface that reflects the light beam from the light source to the object surface is disposed between the light source close to the object surface and the light entrance hole.

The object surface can be illuminated by directly irradiating the object surface with the light rays of the active light source and by reflecting the light rays from the light source onto the object surface by an opposing reflecting surface, and this opposing reflecting surface is connected to the sides of the light source and the light entrance hole. Since the opposing reflective surfaces are located between the opposite reflecting surfaces, the flare of the light source can be blocked by the opposing reflecting surfaces themselves.

Embodiment A first embodiment of the present invention will be explained based on FIG. The same parts as those explained in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted (the same applies hereinafter). The front cover 2 has a light source 11
A protrusion 12a located on one side of the light entrance hole 6 on the side is integrally formed, and an opposing reflective surface 12 facing the light source 11 and the object surface 9 is integrally formed on this protrusion 12a. . The front cover 2 may be formed separately from the housing 1 and fixed to the housing 1, but in this embodiment, the housing 1 and the front cover 2 are integrally formed using aluminum as a material by extrusion molding. After that, the entire surface is subjected to black alumite treatment for antireflection, and then the optical path conversion mirror section 8 and the opposing reflective surface 12 are mirror-finished. Of course, the entire housing l is made of plastic, and the thickness of 0.1 to l m
The optical path converting mirror portion 8 and the opposing reflective surface 12 may be formed by polishing a thin aluminum plate having a thickness of about m and then fixing it to a necessary portion of the front cover 2 by means of adhesive or the like. The optical path changing mirror section 8 is made by depositing a metal such as AQ on a thin glass plate, and is preferably fixed by means such as adhesive, but it can be selected based on a comparison of performance and cost.

tM like this? In this process, the light rays from the light source 11 are directly irradiated onto the object surface 9, and the light rays from the light source 11 are reflected onto the object surface 9 by the opposing reflecting surface 12.
can be illuminated. Moreover, since the opposing reflective surface 12 is located between the light source 11 and the light entrance hole 6, the opposing reflective surface 12 itself can block the flare directed from the light source 11 toward the light entrance hole 6. As a result, light source 1
1 can be brought close to the object surface 9 to effectively illuminate the object surface 9. Furthermore, since the facing reflective surface 12 itself has the function of a light shielding plate for shielding flare light, it can be easily positioned independently and the number of parts can be reduced, thereby reducing the size and cost. You can try to bring it down.

Note that, as shown in FIG. 2, by providing a same-magnification image sensor 13 facing the light exit hole 7, a compact image scanner can be obtained.

Next, a second embodiment of the present invention is shown in FIG.

In this embodiment, light sources 11 and 14 are disposed on both sides of the light entrance hole 6, and opposing reflective surfaces 12 are positioned on both sides of the light entrance hole 6 to irradiate the object surface 9 with the light rays of the light sources 11 and 14, respectively. .15 is integrally formed with the housing l.

Therefore, the illumination effect on the object plane 9 can be further improved. In this case, the opposing reflective surface 15 blocks the flare directed from the light source 14 toward the light entrance hole 6 . As in this embodiment, the light source 11°14 and the opposing reflective surface 12.1
5 are arranged facing each other on both sides of the light entrance hole 6, as shown in FIG. I can do it.

Effects of the Invention Since the present invention is configured as described above, the object surface can be illuminated by directly irradiating the light ray from the light source onto the object surface and by reflecting the light ray from the light source onto the object surface by the opposing reflective surface. In addition, since this opposing reflective surface is located between the light source and the light entrance hole, the opposing reflective surface itself can block the flare from the light source toward the light entrance hole, thereby directing the light source to the object plane. The object surface can be effectively illuminated when brought close together, and the opposing reflective surface itself has the function of a light shielding plate for flare light shielding, so it can be easily positioned independently and the number of parts can be reduced. This makes it possible to achieve miniaturization and cost reduction.Furthermore, by providing a 1-magnification image sensor facing the light exit hole, a compact image scanner can be obtained. have

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional side view showing the first embodiment of the present invention, and the second
The figure is a vertical side view showing a modification thereof, FIG. 3 is a vertical side view showing a second embodiment of the invention, FIG. 4 is a vertical side view showing a modification thereof, and FIGS. 5 to 8 are FIG. 2 is a vertical side view showing a conventional example.

Claims (1)

[Scope of Claims] 1. A housing that includes a lens array in which a plurality of lenses are continuous, a diaphragm that narrows down the light beam, and a roof mirror array in which a plurality of roof-shaped reflective surfaces are continuous; A light entrance hole facing the object surface on which an image is formed and a light exit hole facing the reading unit are formed in a straight line, and a light exit hole is formed in the lens array between the light entrance hole and the light exit hole. An image scanner characterized in that opposing optical path conversion mirror sections are provided, and an opposing reflecting surface that reflects the light rays of the light source to the object surface is disposed between the light source close to the object surface and the light entrance hole. . 2. A housing containing a lens array including a plurality of continuous lenses, a diaphragm for narrowing down the light beam, and a roof mirror array including a plurality of continuous roof-shaped reflective surfaces is placed on a straight line passing through the front surface of the lens array. A light entrance hole and a light exit hole are formed that face the object surface on which an image is formed, and an optical path converting mirror section that faces the lens array is provided between the light entrance hole and the light exit hole, and An opposing reflecting surface that reflects light from the light source onto the object surface is provided between a light source close to the surface and the light entrance hole, and a 1x image sensor is provided facing the light exit hole. Features an image scanner.